O you who believe! If a rebellious evil person comes to you with any news, ascertain the truth, lest you harm people in ignorance, and afterwards you become regretful to what you have done. (Qur'an 49:6)

As
for the relationship between Muhammad bin Abdul-Wahhaab and Ibn
Taymiyah, Abdul-Wahhab was indeed influenced by Ibn Taymiyah. In fact
Abdul-Wahhab started a similar movement at his time. But Abdul-Wahhab had
his da3wa (invitation to Islam) in the heart of the Arabian Desert, while
Ibn Taymiyah in the center of the area and heart of Islam at that time, Sham
(Syria). So he gained much more followers.

Muhammad
Bin Abdul-Wahhab came at a similar time, when in Arabia people started worshipping
stone and grave in the name of Islam. He fought a lot of innovations
and additions to Islam and his efforts succeeded in uniting with the family
of Sa3ud and forming the first Saudi state, but at that time the family of
Saud were righteous people, unlike the family of Saud of today. It is interesting
to note that Abdul-Wahhab and his students were all Hanbalis, just like Ibn
Taymiyah. The first Saudi State ended with the 3rd Ottoman campaign led by
Muhammad Ali Basha himself, but even that failed to erase the methodology.
The methodology is until today widespread in the entire peninsula and not
only Saudi Arabia.

Frankly,
I hear a lot of slander thrown at Muhammad bin Abdul-Wahhab, and I personally
used to dislike him. But when I read his book Kitab
al-Taw7eed and checked the accessions thrown at him I did not find
any of the slander thrown at him truthful. Some cases he is clearly innocent
from what is said, sometimes what they accuse him of is clearly in accordance
with Quran and Sunnah. Like for example the Sufis attack him for destroying
the dooms that were built over the graves of the Companions, but the fact
is there are many Hadeeths that say that such things are the actions of the
Jews and Christians, and that those who build such things are the worst of
the creation and that the Prophet cursed such a thing, and that he strictly
forbade such a thing. So as you see, those who attack him are either ignorant
about the Sunnah or are just venting out hatred against Arabs.

Some
of the other innovation Abdul-Wahhab students canceled, was the innovation
of performing four prayers one for each school (mathab). Like a Hanafi would
do Athan (call prayer) and then all the Hanafis would perform the prayer behind
a Hanafi Imam, then a Maliki would do Athan and the Malikies would do their
prayer and so on. Abdul-Wahhab students canceled this and praying in the Ka3ba
returned to be unity like it was at the days of the Companions and like it
is today, thanks for Allah.

In
fact if Abdul-Wahhab is what I know about him by now, then he is Insha' Allah
another reformer (Mujadid) like Ibn Taymiyah: he revived the forgotten of
the Sunnah, he fought innovations, and he returned the people to the understanding
of the Companions.

As
for the Wahhabi Da'wa today, most Wahhabi people live in Saudi Arabia. Almost
all people in Mecca and Medina belong to this school. They don't use the term
Wahhabi, but rather, Salafi Da'wa or Ahlul Sunna wal Jama'a. Although, they
have a negative view about women and some modern inventions, they played in
important role to keep Islam alive in Arabia. They also played a significant
role in raising up Islam and resisting missionary Christians in the Muslim
world. Many people think that Wahhabi people are bad because the King of Saudi
Arabia is bad. This assumption is clearly wrong since the Saudi king does
not follow that school. His
jails are full with Wahhabi scholars. Some people
(unfortunately) slander Wahhabis as a way to slander Arabs. If you want to
know the truth about those people, I advice you to check this site that is
maintained by a famous Wahhabi scholar:www.Islam-qa.com
and check out www.usc.edu/dept/MSA

Ultimately, I advice all Muslims:
Do not judge people before you listen to them.